<?php

	/**
	 * Handle file uploads via XMLHttpRequest
	 */
	class qqUploadedFileXhr {
	    /**
	     * Save the file to the specified path
	     * @return boolean TRUE on success
	     */
	    function save($path) {    
	        $input = fopen("php://input", "r");
	        $temp = tmpfile();
	        $realSize = stream_copy_to_stream($input, $temp);
	        fclose($input);
	        
	        if ($realSize != $this->getSize()){            
	            return false;
	        }
	        
	        $target = fopen($path, "w");        
	        fseek($temp, 0, SEEK_SET);
	        stream_copy_to_stream($temp, $target);
	        fclose($target);
	        
	        return true;
	    }
	    function getName() {
	        return $_GET['qqfile'];
	    }
	    function getSize() {
	        if (isset($_SERVER["CONTENT_LENGTH"])){
	            return (int)$_SERVER["CONTENT_LENGTH"];            
	        } else {
	            throw new Exception('Getting content length is not supported.');
	        }      
	    }   
	}
	
	/**
	 * Handle file uploads via regular form post (uses the $_FILES array)
	 */
	class qqUploadedFileForm {  
	    /**
	     * Save the file to the specified path
	     * @return boolean TRUE on success
	     */
	    function save($path) {
	        if(!move_uploaded_file($_FILES['qqfile']['tmp_name'], $path)){
	            return false;
	        }
	        return true;
	    }
	    function getName() {
	        return $_FILES['qqfile']['name'];
	    }
	    function getSize() {
	        return $_FILES['qqfile']['size'];
	    }
	}
	
	class qqFileUploader {
	    private $allowedExtensions = array();
	    private $sizeLimit = 10485760;
	    private $file;
	
	    function __construct(array $allowedExtensions = array(), $sizeLimit = 10485760){        
	        $allowedExtensions = array_map("strtolower", $allowedExtensions);
	            
	        $this->allowedExtensions = $allowedExtensions;        
	        $this->sizeLimit = $sizeLimit;
	        
	        $this->checkServerSettings();       
	
	        if (isset($_GET['qqfile'])) {
	            $this->file = new qqUploadedFileXhr();
	        } elseif (isset($_FILES['qqfile'])) {
	            $this->file = new qqUploadedFileForm();
	        } else {
	            $this->file = false; 
	        }
	    }
	    
	    private function checkServerSettings(){        
	        $postSize = $this->toBytes(ini_get('post_max_size'));
	        $uploadSize = $this->toBytes(ini_get('upload_max_filesize'));        
	        
	        if ($postSize < $this->sizeLimit || $uploadSize < $this->sizeLimit){
	            $size = max(1, $this->sizeLimit / 1024 / 1024) . 'M';             
	            die("{'error':'increase post_max_size and upload_max_filesize to $size'}");    
	        }        
	    }
	    
	    private function toBytes($str){
	        $val = trim($str);
	        $last = strtolower($str[strlen($str)-1]);
	        switch($last) {
	            case 'g': $val *= 1024;
	            case 'm': $val *= 1024;
	            case 'k': $val *= 1024;        
	        }
	        return $val;
	    }
	    
	    /**
	     * Returns array('success'=>true) or array('error'=>'error message')
	     */
	    function handleUpload($uploadDirectory, $replaceOldFile = FALSE){
	        if (!is_writable($uploadDirectory)){
	            return array('error' => "Server error. Upload directory isn't writable.");
	        }
	        
	        if (!$this->file){
	            return array('error' => 'No files were uploaded.');
	        }
	        
	        $size = $this->file->getSize();
	        
	        if ($size == 0) {
	            return array('error' => 'File is empty');
	        }
	        
	        if ($size > $this->sizeLimit) {
	            return array('error' => 'File is too large');
	        }
	        
	        $pathinfo = pathinfo($this->file->getName());
	        $filename = $pathinfo['filename'];
	        //$filename = md5(uniqid());
	        $ext = $pathinfo['extension'];
	
	        if($this->allowedExtensions && !in_array(strtolower($ext), $this->allowedExtensions)){
	            $these = implode(', ', $this->allowedExtensions);
	            return array('error' => 'File has an invalid extension, it should be one of '. $these . '.');
	        }
	        
	        if(!$replaceOldFile){
	            /// don't overwrite previous files that were uploaded
	            while (file_exists($uploadDirectory . $filename . '.' . $ext)) {
	                $filename .= rand(10, 99);
	            }
	        }
	        
	        if ($this->file->save($uploadDirectory . $filename . '.' . $ext)){
	            return array('success'=>true);
	        } else {
	            return array('error'=> 'Could not save uploaded file.' .
	                'The upload was cancelled, or server error encountered');
	        }
	        
	    }    
	}
	
	// list of valid extensions, ex. array("jpeg", "xml", "bmp")
	$allowedExtensions = array();
	// max file size in bytes
	$sizeLimit = 100 * 1024 * 1024;
	
	$uploader = new qqFileUploader($allowedExtensions, $sizeLimit);
	$result = $uploader->handleUpload('../files/');
	
	$result['get'] = $_GET;
	
	// to pass data through iframe you will need to encode all html tags
	echo htmlspecialchars(json_encode($result), ENT_NOQUOTES);
